OCTAGON
ADJECTIVES
► EIGHT-SQUARE having eight equal sides; octagonal → 1538 obs. exc. nautical usage
► OCTAGONIAN belonging to an octagon → 1813 obs.
NOUNS
► EIGHT-SQUARE an octagonal figure → 1794
► OCTANGLE a figure with eight angles, an octagon → 1651 obs.
VERBS
► EIGHT-SQUARE to fashion into octagonal shape → 1794
Lexicophilia 